1onx | pdb_00001onx

Crystal structure of isoaspartyl dipeptidase from escherichia coli complexed with aspartate

spinqualitylabelsall models 1onx, resolution 2.10Å Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image   Print3D Structural highlights 1onx is a 2 chain structure with sequence from Escherichia coli. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance. Method: X-ray diffraction, Resolution 2.1Å Ligands: ASP, KCX, ZN Resources: FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT Function IADA_ECOLI Catalyzes the hydrolytic cleavage of a subset of L-isoaspartyl (L-beta-aspartyl) dipeptides. Used to degrade proteins damaged by L-isoaspartyl residues formation. The best substrate for the enzyme reported thus far is iso-Asp-Leu. Evolutionary Conservation Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMed Isoaspartyl dipeptidase from Escherichia coli functions in protein degradation by catalyzing the hydrolysis of beta-L-isoaspartyl linkages in dipeptides. The best substrate for the enzyme reported thus far is iso-Asp-Leu. Here we report the X-ray analysis of the enzyme in its resting state and complexed with aspartate to 1.65 and 2.1 A resolution, respectively. The quaternary structure of the enzyme is octameric and can be aptly described as a tetramer of dimers. Each subunit folds into two distinct domains: the N-terminal region containing eight strands of mixed beta-sheet and the C-terminal motif that is dominated by a (beta,alpha)(8)-barrel. A binuclear zinc center is located in each subunit at the C-terminal end of the (beta,alpha)(8)-barrel. Ligands to the binuclear metal center include His 68, His 70, His 201, His 230, and Asp 285. The two zincs are bridged by a carboxylated lysine residue (Lys 162) and a solvent molecule, most likely a hydroxide ion. The product of the reaction, aspartate, binds to the enzyme by displacing the bridging solvent with its side chain functional group. From this investigation it is proposed that the reaction mechanism of the enzyme proceeds through a tetrahedral intermediate and that the bridging solvent attacks the re face of the carbonyl carbon of the scissile peptide bond. This structural analysis confirms the placement of isoaspartyl dipeptidase into the urease-related amidohydrolase superfamily. High-resolution X-ray structure of isoaspartyl dipeptidase from Escherichia coli.,Thoden JB, Marti-Arbona R, Raushel FM, Holden HM Biochemistry. 2003 May 6;42(17):4874-82. PMID:12718528 From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See Also Isoaspartyl dipeptidase

Proteopedia Page Contributors and Editors (what is this?)

OCA